To form a flange on a sheet metal panel using a die, two cams are generally used. The first cam is a filler cam or anvil and the other cam is the form cam that forms or flanges the sheet metal around the filler cam. The filler cam is retracted after the forming process so the formed or flanged panel can be removed. The process may then be started over.
There are several types of cams that perform the above function. Of the types of cams that are available, a rotary filler cam is regarded as the best because these types of cams are able to fit into tight conditions. Rotary filler cams work in conjunction with an aerial form cam to form or flange the sheet metal panel. These types of cams, however, are expensive and are generally manufactured overseas.
Further, the use of an aerial form cam in conjunction with the rotary filler cam has drawbacks in that the aerial form cam is mounted to the upper die and can interfere with automation curves during panel transfers in the press, which can lead to process and styling changes. Moreover, aerial form cams are heavy and can add unbalanced weight to the upper die and press. This may present a problem when separating the die during construction, maintenance, and repair.